• Fisheries and Aquatic Sciences
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• 제21권11호
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• pp.31.1-31.7
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• 2018

Three economic marine algae that have been used as food and carrageenan sources were collected from Korea during a survey of marine algal flora. They share the generic features of Hypnea, and three major clades supported by the sectional features were confirmed in a phylogenetic tree based on rbcL sequences. The first species, which belongs to a species group corresponding to the sect. Spinuligerae, nests in the same clade with Hypnea yamadae in a genetic distance of 0%. It is morphologically characterized by an entangled base, subcompressed or subterete to terete axes, somewhat percurrent main axis, irregularly alternately branching with wide angle, and rarely hooked spinous branchlets. The second one is also referred to the sect. Spinuligerae and formed the same clade as Hypnea cenomyce. The genetic distance between both sequences was calculated as 0.0-0.1%, which is considered to be intraspecific. This species is distinct by somewhat entangled thallus at the basal part, percurrent axis, short spine-like branchlets densely covering the axis, and medullary lenticular thickenings. The third alga, which forms a species group corresponding to the sect. Pulvinatae, nests in the same clade as Hypnea nidulans (no intraspecific divergence). It shows occasionally epiphytic habitat rather than epilithic habitat of low mat-forming growth and percurrent erect main axes with dense lateral branchlets. Based on these morphological and molecular data, the three Korean species are identified as H. yamadae, H. cenomyce, and H. nidulans. This is the first record of the Hypnea species in Korea.

• 생명과학회지
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• 제17권3호통권83호
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• pp.328-333
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• 2007

한국내 분포하는 맥문동(Liriope platyphylla) 11집단에 대한 20 알로자임 대립유전자좌위에서 유전적 다양성과 집단구조를 조사하였다. 효소내 다형성을 나타내는 빈도는 55.9%였다. 종과 집단 수준에서 유전적 다양도는 각각 0.178, 0.168로 높았으며, 집단간 분화 정도는 낮았다($G_{ST}$ = 0.064). 전체 11 집단에서 임의교배에 의한 편차는 0.311이였다. 전체 유전적 다양성는 $0{\sim}0.535$였다. 유전적 다양도 중 집단내 변이는 높았다($H_S$ = 0.305). 세대간 이주하는 개체수는 약 3.66으로 이 종의 한국내 집단간 유전자 흐름이 높음을 시사한다. 또한 라이트의 고정지수 분석 결과 많은 대립유전자좌위와 집단에서 이형접합자의 결핍이 존재하고 있었다. 집단간 유전적 동질성은 0.988이였다. 이는 맥문동의 분포지가 한국내 유사한 환경에 놓여 있고 집단이 방향적 동질성을 가지고 있음을 시사한다.

• 환경생물
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• 제35권3호
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• pp.329-334
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• 2017

A marine ulvalean species (Chlorophyta) was collected from Imgok, which is located on the eastern coast of Korea. This species is morphologically characterized by distromatic, filiform to strap compressed or tubular thallus. Many branches were found near the base, but lacked proliferations. Cells were longitudinally aligned in the younger part of the branch and were disordered in the older part of the branch. A cap-like parietal chloroplast with one or two pyrenoids was contained in each cell. In a phylogenetic tree based on ITS and rbcL sequences, this species was nested in the same clade as Ulva torta and U. clathratioides from Australia, but formed a sister clade to U. torta from Japan. However, the genetic divergence between them was included in an intraspecific variation range within Ulva. This finding suggests that U. clathratioides should be reduced to a synonym of U. torta. Accordingly, the Korean alga was identified as U. torta based on the morphological and molecular data. This investigation is the first record of U. torta in the Korean marine algal flora.

• 환경생물
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• 제37권3호
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• pp.362-366
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• 2019

A marine green algal species (Chlorophyta) was collected from the eastern coast of Korea. It is morphologically characterized by monostromatic thallus, usually undulate and entire margins, cap-like chloroplast and several pyrenoids per cell. In a phylogenetic tree based on molecular data, the Korean alga nests in the same clade as Monostroma alittorale originally described from Japan, as a sister clade of M. grevillei from France. The genetic distance for ITS(Internal Transcribed Spacer) sequences among Monostroma species ranges from 2.3% to 38.2%. The value between the Korean entity and M. alittorale was calculated as 0.01%, considered to be intraspecific divergence. This Korean entity is identified as Monostroma alittorale based on morphological and molecular analyses. This is the first record of M. alittorale in Korea.

• 환경생물
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• 제37권3호
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• pp.293-298
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• 2019

A marine ulvalean species (Chlorophyta) was collected from the eastern coast of Korea. This species is morphologically characterized by a distromatic, dark to medium green and mostly irregularly orbicular or irregularly expanded thallus with entire or undulate margin without serrations. Vegetative cells are irregularly polygonal with distinctly rounded corners in shape, and have chloroplast completely covering the outer cell wall and one to two pyrenoids per cell. In a phylogenetic tree based on ITS (Internal Transcribed Spacer) sequences, this Korean alga nests in the same clade with Ulva sublittoralis, as a sister clade of U. californica, U. flexuosa and U. tanneri, which share the irregularly orbicular or expanded thallus normally without teeth cells. The genetic divergence between them is intraspecific within Ulva. Accordingly, it is identified as U. sublittoralis based on the morphological and molecular data. This is the first record of Ulva sublittoralis in the Korean marine algal flora.

• Genomics & Informatics
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• 제10권4호
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• pp.226-233
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• 2012

Since the advent of whole-genome sequencing, transposable elements (TEs), just thought to be 'junk' DNA, have been noticed because of their numerous copies in various eukaryotic genomes. Many studies about TEs have been conducted to discover their functions in their host genomes. Based on the results of those studies, it has been generally accepted that they have a function to cause genomic and genetic variations. However, their infinite functions are not fully elucidated. Through various mechanisms, including de novo TE insertions, TE insertion-mediated deletions, and recombination events, they manipulate their host genomes. In this review, we focus on Alu, L1, human endogenous retrovirus, and short interspersed element/variable number of tandem repeats/Alu (SVA) elements and discuss how they have affected primate genomes, especially the human and chimpanzee genomes, since their divergence.

• BMB Reports
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• 제48권7호
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• pp.373-379
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• 2015

Humans have acquired many distinct evolutionary traits after the human-chimpanzee divergence. These phenotypes have resulted from genetic changes that occurred in the human genome and were retained by natural selection. Comparative primate genome analyses reveal that loss-of-function mutations are common in the human genome. Some of these gene inactivation events were revealed to be associated with the emergence of advantageous phenotypes and were therefore positively selected and fixed in modern humans (the "less-ismore" hypothesis). Representative cases of human gene inactivation and their functional implications are presented in this review. Functional studies of additional inactive genes will provide insight into the molecular mechanisms underlying acquisition of various human-specific traits. [BMB Reports 2015; 48(7): 373-379]

• 한국수산과학회지
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• 제29권6호
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• pp.876-881
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• 1996

To determine the amount of genetic variation among populations of Penaeus chinensis (Osbeck) in the Yellow Sea, 342 bp region of the mitochondrial cytochrome c oxidase subunit I gene was amplified and sequenced. Six haplotypes, which differ by from one to four nucleotide sustitutions, were detected from 34 individuals of 4 populations examined. Mean sequence divergence between pairs of haplotypes was $0.68\%$. Most individuals from 4 populations were shared by the most common genotype. This genotype was distributed evenly in the Korean and Chinese populations. This result is in accordance with findings observed using RFLPs analysis of mtDNA (Hwang et al., 1997). Therefore, it is suggested that P. chinensis should be treated as one unit stock in the Yellow Sea.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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• pp.497-498
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• 2000

The venus clam, Ruditapes philippinarum, is an aquaculture shellfish mainly distributed in an intertidal zone of East Asia including Korea, China and Japan. The morphological variation of this species is great. In fact, two of the most popular markers used in molecular evolution, mitochondrial DNA (mtDNA) and nuclear ribosomal DNA (rDNA), have quite different properties, which could translate into different consequences of mutation, drift, migration and selection on patterns of geographical variation and molecular divergence. (omitted)

• 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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• 한국정보과학회언어공학연구회 2013년도 제25회 한글 및 한국어 정보처리 학술대회
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• pp.107-109
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• 2013

주식 시장에서 거래되고 있는 증권은 MACD(Moving Average Convergence Divergence), Stochastic 등의 보조 지표를 이용하는 기술적 분석을 통하여 매수/매도 시점을 결정한다. 주식 시장의 객관적인 자료를 통하여 분석하는 기술적 분석 방법은 주식 시장 외적인 요소를 반영하는데 있어 한계점이 존재한다. 본 논문에서는 기술적 분석 방법에 기사를 종목별로 분류하고 기사의 긍정 및 부정을 판별하는 문서 분류 기법을 적용하여 주식 외적인 요소를 반영하는 시스템을 제안한다.